Final answer:
The secretory cells of exocrine and endocrine tissues are typically grouped into structures known as glands. Exocrine glands release their secretions through ducts, while endocrine glands release hormones directly into the bloodstream.
Step-by-step explanation:
The secretory cells of the exocrine and endocrine tissues are often grouped into structures called glands. Exocrine glands release their products through ducts to various surfaces, including the skin or into the lumen of the gastrointestinal tract, making their contents external to the body.
Examples include mucous, sweat, and salivary glands. On the other hand, endocrine glands secrete hormones directly into the interstitial fluid and bloodstream, which carries these hormones to target organs throughout the body.
Glandular structure can be classified based on the method of secretion or the structural organization, such as merocrine, apocrine, and holocrine for secretion methods, and tubular or alveolar (acinar) in terms of structure.